The recent wars in Iraq and Afghanistan have raised important questions about the future direction of U.S. foreign policy and how Americans can best exercise power abroad in the coming years. Commentators have not shied away from offering advice. Some defend the record of the George W. Bush administration and blame Barrack Obama’s “weakness” for the current disorder that wracks large sections of the Middle East. In their view, the United States must continue to carry out “unilateral” military campaigns when necessary to preempt “terrorist” threats and work to spread democratic government all over the world. It also needs to maintain unquestioned military superiority to deter the aggressive plans of countries like China, Russia, and Iran.

Many authors reject the general thrust of these arguments. For some, Americans need to focus more attention on implementing “a realistic” foreign policy that avoids “crusades for democracy” and protects genuine U.S. interests as the world becomes multipolar. No doubt influenced by authors who have either predicted or announced the arrival of a “post-American world,” others have implored U.S. policymakers to address important domestic problems like income inequality and strengthen international institutions designed to promote “global governance.” In a similar vein, a number of commentators have rejected any suggestion that George W. Bush’s policies represent a legitimate form of “Wilsonianism.” If Americans policymakers want to become the “true heirs” of Wilson, they need to strengthen “global governance” and work through the United Nations to gain the “legitimacy” needed when the exercise of military power abroad becomes unavoidable.

The political scientist Henry R. Nau (George Washington University) enters debates about the conduct of U.S. foreign policy in his new book Conservative Internationalism: Armed Diplomacy under Jefferson, Reagan, Truman, and Polk (Princeton University Press, 2013). Not one to shy away from controversy, Nau argues that authors have made a fundamental mistake when they offer advice to U.S. policymakers without reference to an important American foreign policy tradition that he defined as “conservative internationalism.” To help readers gain a better grasp of this approach, he includes detailed case studies that highlight the foreign policy successes of Thomas Jefferson, James Polk, Harry Truman, and Ronald Reagan. More than most realize, Nau contends, these Presidents combined the use of force and effective diplomacy in ways that expanded the boundaries of freedom and handled threats in ways that did not allow them to become more costly problems for their successors.

Although many critics will question the lessons that Nau draws from his Presidential case studies and analysis of events from 1991 to the present, they will be hard pressed to deny the relevance of his new book. He reminds readers that this “imperfect” world will not necessarily become a better place if the United States chooses to turn inward and fails to deal with the wide array of threats that could potentially undermine the contemporary global order. Nau also offers thought provoking insights on how the disciplined use of military power and “realistic” promotion of democratic government can serve U.S. interests quite well in the years ahead. Enjoy.